Integrated roller unit

ABSTRACT

The invention relates to roller unit consisting of an inductively heated roller, a drive motor, an inductor and a frequency converter. According to the invention not only the converter but also the temperature regulator for the induction heater and monitoring devices for the roller, heater and/or motor are integrated into the roller unit. The power electronics and the regulator are mounted on a common cooling unit which is cooled by a coolant which at the same time also cools the motor, the bearings and the inductor.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage of PCT/EP 99/069,44 filed Sep. 20,1999 and based upon German National application 198 43 990.3 of Sep. 20,1998 under the International Convention.

FIELD OF THE INVENTION

The present invention relates to an inductively-heated gallet or godetfor the treatment of synthetic fibers or yarns and is directed to astructure which is simultaneously advantageous for installation, set-up,operation and maintenance. It should be noted that a textile machineusually has a multiplicity of such godets which are supplied withoperating parameters by a control computer for speed and temperature.

BACKGROUND OF THE INVENTION

From EP 0 235 505 B1 and EP 0 424 867 B1 it is known to cool the motor,inductor and bearings of inductively heated godets with air or liquid.For numerous industrial purposes, so-called integral motors comprised ofa motor and frequency converter have been provided (compare Journal“PRODUKTION” of April 2 1998, No. 14, page 15). A blower cooling for agodet unit, motor and converter is described in DE 197 26 258 A1 wherethe frequency converter is encapsulated in a housing in a heat transferstate in which, for heat dissipation, the surface provided with coolingribs is cooled by a blower. For this purpose, the converter housing isprovided with a common axis with the motor and on the opposite side ofthe motor from that of the godet in a cup-shaped godet housing whichalso encloses the motor and in whose bottom region a blower impellerseparately driven by a fan motor displaces cooling air initially overthe converter housing and then over the godet motor.

SUMMARY OF THE INVENTION

A godet assembly according to the invention can be affixed on a machineframe of a yarn processing apparatus and is provided with an inductivelyheatable godet and a drive motor, whereby a frequency converter for themotor, a controller serving as a temperature regulator for the heater aswell as monitoring devices for the godet for the heater and/or for themotor are integrated in the godet assembly.

With the invention, a compact and integrated godet assembly is obtainedwhich is especially suitable both for high thread load (thermal loading)and high speed. The important advantage of the assembly of godet,frequency converter/drive, temperature regulator and monitor device toan integrated unit resides in that no separately conditioned space isrequired as the control and circuitry closet and the cabling costs aresharply reduced. The overall unit, i.e. the mechanics of the motor driveas well as the heat control, is completely testable before it isinstalled in the textile machine so that long start-up times of themachine and possible installation defects are avoided. In case a unitreplacement is required, the production fall-out time is significantlyreduced because the replacement unit can be fully tested mechanicallyand electrically before installation. Environmental influences arelargely excluded because of the compact construction of the electroniccircuitry in the unit itself and the suitable cooling thereof. Inaddition, the incorporation of the electronic circuitry directly in theunit allows the measurement and monitoring of additional physical andelectrical parameters without requiring therefore expensive cabling. Theelectromagnetic inertia of the overall system is significantly improvedbecause of the compact construction and the short cables.

The frequency converter, the controller and the monitoring circuitry canbe incorporated in a sealed housing which is directly affixed to thegodet unit and is electrically connected with it. As the singleelectrical connection to the exterior, an alternating current terminalfor the heating power, a direct current terminal for the converter aswell as a data base terminal to a computer can be provided. The godetassembly can have air cooling of the power circuitry. The powercircuitry and the controller can be mounted on a heat conductive coolingblock which is well conducting and which is in good heat conductingrelationship with an outer protective housing. The preferablycylindrical protective housing can be provided with axial cooling ribs.The blower can be arranged as a cooling blower in the axial direction ofmotor and godet between the drive motor and the cooling block. Theblower roller can be affixed to the godet. The godet assembly can alsohave liquid cooling, the converter and controller are carried by ahollow liquid cooled cooling block. In the axial direction of the motorshaft between the cooling block and godet holder or support flange themotor housing is provided with coolant passages or a coolant annulargap. Further coolant passages can be provided for cooling the shaftbearing. In the inductively heated godet, additional coolant passagesand spaces can be provided in the region of the heating inductor and/orthe hub of the godet. A bearing housing carrying at least the bearingremote from the motor and can extend into the godet shell and theinductor. The bearing remote from the motor can be located approximatelyat the center of gravity of the godet. The configuration of the coolingpassages is such that the cooling liquid initially flows through thecooling block, then through the motor cooling passages and then throughan annular space surrounding the godet hub and then through a coolingpassage for the bearing and inductor before it flows to the coolantoutlet. The components of the converter can be mounted on a cover plateand the components of the controller can be mounted on the oppositecover plate of a hollow substantially rectangular cooling block. Thecooling block can be affixed to the end wall furthest from the godet ofthe motor housing. Between the cooling block and the wall or ring platecarrying same, a thermal and/or mechanical insulating intermediate layeris provided. The cooling block can be surrounded by a sealed protectivehood. The assembly two spaced-apart shaft bearings, and the shaftbearing furthest from the motor is disposed within the integrator and iscarried by a bearing housing surrounding shaft, while a support flangewhich serves to affix the unit on the machine frame extends into theinterior of the integrator. The bearing housing can serve simultaneouslyto support the integrator. The inductor can be comprised of an inductorsupport tube held by the support flange, an inductor core preferably ofelectromagnetic sheet surrounding the support tube and an excitingwinding on the inductor core.

The inductor support tube and the bearing housing there is an annulargap which is sealed in axial direction on both sides by elastic sealingrings which simultaneously serve as vibration damping between theinductor and the bearing housing. A bearing temperature sensor can bearranged in the region of the bearing furthest from the motor. One ofthe bearings can be located in the region of the support flange. Anasynchronous drive motor which can be used and can be controlled by thecontroller taking into consideration the slip frequency of the drivemotor for simultaneously synchronous speed regulation. The transmissionof temperature measurement signals from the godet to the controller iseffected by a rotating measuring value transmitter serving as a pulsegenerator for signals serving for speed regulation. The controller canmeasure the torque by the slip of the asynchronous motor and thusdetermines the thread tension.

The monitoring device can monitor, in addition to the godettemperatures, the bearing temperatures and the inductor temperaturesalso other physical and/or electrical magnitudes like vibration, coolingwater and motor temperature, motor current and supplies warning orsafety shutdown signals derived therefrom.

A common cooling of the electronic power circuitry, motor, bearings andother parts of the unit, e.g. the inductor, can be carried out in amanner known per se (compare EP 0 424 867) with intrinsic or externalventilation. For this purpose preferably a carrier or cooling bodyenclosed by a cylindrical housing or housing part is connected to theblower and is constructed to receive the power electronic circuitry andthe controller such that this electronic housing lies on the suctionside of the blower and the motor as well as its bearing lie on itspressure side. The blower impeller can either be driven by the godetmotor (intrinsic ventilation) or by a separate fan motor (externalventilation).

The cooling by means of a cooling liquid, for example, the cold water ofa coolant unit, enables cooling of the power electronic circuitry andthe controller independently of ambient temperature and the intrinsicheating of the unit. With liquid cooling the godet motor requires noadditional drive power for the blower. A common cold water supply forthe electronic power circuitry, motor and bearing has a single coldwater connection for the unit.

BRIEF DESCRIPTION OF THE DRAWING

The invention is described below in greater detail with reference to twoembodiments illustrated in the drawing. It shows in

FIG. 1 a godet unit with water cooling in sections along the godet andmotor axis;

FIG. 2 an elevation of the godet end;

FIG. 3 an elevation of the back side of the unit with cover removed sothat the cooling block with the power electronic circuitry andcontroller is visible;

FIG. 4 a godet unit with air cooling in the form of intrinsicventilation in section along the godet and motor axis; and

FIG. 5 a plan view of the end of the godet housing turned away from thegodet.

SPECIFIC DESCRIPTION

A yarn processing machine is usually equipped with a multiplicity ofsuch godet units which are supplied via a bus from a control computerwith feed signals and temperature signals as well as with current supplylines with current for the motor and heater.

In the case of the godet unit illustrated in FIGS. 1 to 3 with watercooling, the cold water fittings are connected with self-sealingjunctions for example to the cold water network of a coolant apparatusor to a separate cooler. A support flange 1 affixed to the machine frameholds a tube piece 21 extending into the godet shell 2 and the inductor.The illustrated multizone inductor here comprises a support tube 3, acore 4 preferably of electromagnetic sheet and the exciting coils 5. Thetube piece 21 serves on the one hand as a bearing housing for supportingthe two bearings 22 and 24. In that case, the bearing 22 close to themotor is located in the region of the support flange 1 while the bearing24 remote from the motor lies proximally at the center of gravity of thegodet and is held by the end region 23 of the bearing housing 21 remotefrom the flange. On the other hand, the tube piece 21 supports theinductor carrying the tube 3. The latter is braced via sealing ring 42and thus also an elastic element against the flange on the bearinghousing 21 and forms between itself and the inductor carrying tube 3 ahollow space which serves for cooling purposes. The illustratedconfiguration of the mounting of the shaft and inductor results in amechanical decoupling between the inductor carrying tube and bearinghousing 21 so that on the one hand mechanical vibration resulting froman electrical excitation of the inductor is not transferred to the shaftbearing and on the other hand, vibrations resulting from eccentricity ofthe rotating parts, shaft/godet, are not transferred to the inductor. Bysuitable choice of the spring constants and the number of O-rings 42,one can influence the characteristic resonance frequency of the unit.

On the free end 6 of the drive shaft 7 is seated the hub of the godetwhose shell 2 is connected with the shaft 7. The other end part 9 of theshaft 7 carries the rotor 10 of the motor whose stator 11 and housing 12are also affixed on the support flange 1. The motor housing 12 is thuscomprised of a hollow cylindrical shell 13 and two ring plates 14 and 15at its ends. The ring plate 14 proximal to the flange is provided with ascrew connection with the carrying flange 1. At the shaft end 16extending through the ring plate 15 remote from the flange has arotating part 17 of a measured value transmitter attached thereto andwhose stationary part is held on the ring plate 15. From the rotatingpart 17 conductors 18 extend through the hollow shaft 7 to an insulatedsensor terminal plate 19 and from there to temperature sensors which areembedded in bores of the godet shell 2. The sensor terminal plate 19 isclosed toward the exterior with a cover 20 which has conductor tracksthereon and protects the end of the device.

In the embodiment of water cooling according to FIGS. 1 to 3, on thering plate 15 remote from the flange, a cooling block 26 is mounted viaan angle piece 25, the cooling block having a coolant inlet 27 and acoolant outlet 28. An intermediate layer 29 insulates the angle piece 25and thus the cooling block 26 from vibration and thermally from ringplate 15 and thus from the motor. The cooling block 26 in thisembodiment is illustrated as a rectangular hollow body which, in itsinterior can be subdivided by flow guide means into a multiplicity ofchannels in the cooling block longitudinally extending in, for example,the flow direction. As FIG. 3 shows on one cover plate of the coolingblock 26 the power semiconductor 30 is mounted with a microcomputer 30Aas well as the usual assembly of converters while on the opposite coverplate the components 31 of the controller for the godet unit can befastened in good conducting relationship so that frequency converter andcontroller are thermally decoupled. This ensures a temperatureindependent operation of the controller. The output of the converter isconnected via a cable 32 with the exciting coils 5 of the inductor. Thecontroller 31 controls on the one hand via the converter 39, 30A theheating power supplied to the inductor and on the other hand the speedof the motor. For this purpose it receives the supply alternatingvoltage via the supply cable 33 for the heater 4, 5, via a cable 33A thedirect current for the converter 30, 30A and via a bus 33B the controlparameters for the controller in the form of temperature and speedsignals from the computer associated with the machine. The bearing 24remote from the motor is provided on its inner and/or outer ring withtemperature sensor 45 whose output signal is used by controller 31 to socontrol the amount of the cooling medium by means of an electricalcontrol valve for all operating states of the unit with both theabsolute bearing temperature and also the temperature difference betweencritical values predetermined between the inner and outer ring will notbe exceeded. By the use of an asynchronous motor, the controller 31 alsoassumes synchronous speed regulation in that it can monitor the slipfrequency of the motor for the control of the converter 30, 30A. Forthis purpose, the measured value transmitter 17 can additionally beprovided with a pulse generator whose output signal is used for speedregulation. The controller 31 can detect in addition, the slip of theasynchronous motor and thus the torque, i.e. the thread tension.Finally, with the controller or a monitoring device associatedtherewith, still other physical and electrical parameters, likevibration, cooling water temperature, motor temperature, motor currentor the like can be detected. Aside from the godet temperature, thebearing temperatures and the inductor temperature and warning signals orsafety shutdown signals can be provided. After the coolant suppliedthrough the coolant inlet 27, preferably cold water through the coolinginlet 27 has passed through the cooling block 26, it leaves through theoutlet 28 and cooling passage 34 or an annular gap 34 in the motorhousing 12 so that an effective liquid cooling of the motor is assured.Then the cooling water flows through the passage 35 and the passages 36and 37 in the bearing housing 21 to the front annular chamber 38surrounding the hub 8. The passages 36 are uniformly distributed overthe periphery of the bearing housing 21 to cool in this manner the outerring of the bearings 22 and 24. From the annular space 38 the nowalready warm cooling water passes through a connecting passage not showninto the annular gap 39 between the bearing housing 21 and the inductorsupport tube 3. Finally, a passage 40 connects this annular space 39with the cold water return line 41. The cold water supplied by a singlecold water supply line 27 thus cools in the following sequence theindividual components of the assembly: power electronic circuitry 30 andcontroller 31, motor 9-15, the hub 8 of the godet, the bearing 22, theinductor 3, 4, 5 and finally the bearing 24. As a result, the cooling ofthe entire unit is unusually effective, whereby the components requiringthe greatest cooling (the power electronic circuitry) lies at the startof the cooling chain. A protective hood comprised of a cylindrical shell43 and a common wall 44 surrounds the cooling block 26 and is providedwith sealed throughgoing openings for the cable connectors 33, 33A and33B as well as for the cold water supply line 27. These connectors arepreferably configured as plug connectors. As FIG. 1 shows, the bearinghousing 21 has a longitudinal bore 44A which extends from the flange 1up to the outer ring of the bearing 24 and which receives a temperaturesensor 45 for measuring the temperature of this bearing. The cold watersupply is so controlled by the controller 31 and a cold water meteringvalve that with every conceivable operating mode, no bearing overheatingcan arise and also there is no impermissible high temperature differencebetween the inner and outer ring of the bearing 24.

The second embodiment illustrated in FIGS. 4 and 5 of the integratedgodet unit operates with air cooling and, indeed, with intrinsicventilation. The mechanical construction of the godet and motor as wellas the cooling air flow along the motor and in the region of theflange-side bearing, corresponding substantially to that of thearrangement in EP 0424 867 B1 and thus need not be described again indetail. On the shaft end of the motor projecting out of the bearingshield 46, there are provided in succession the fan 47 and the rotatingpart 17 of the measured value transmitter. On one side of a coolingblock 26 which is of good thermal conductivity or on a separate suitablecarrier are mounted the power electronic circuitry 30 and themicrocomputer 30A. The components of the controller 31 are mounted forexample on the opposite side. A cylindrical shell 43 provided with axialcooling ribs, forms together the end wall 44 a protective hood whichencloses the cooling block 26 serving as the circuitry carrier and is ingood thermal contact therewith so that the cooling air sucked by the fanpasses for example outwardly along the cooling ribs or between thelatter or between the latter and an outer housing shell so that thecooling air passes initially to cool the circuitry before it is forcedinto the cooling passages of the motor housing and then passes in thevicinity of the support flange along the bearing 24 proximal to thegodet. The current supply lines 48 for the motor and the heating currentlines 49 for the inductor run at least partly in respective coolinglongitudinal channels 50 of which a multiplicity are provided in spacedrelationship over the periphery of the motor.

What is claimed:
 1. A godet assembly comprising: support means foraffixing said assembly to a machine frame of a yarn processing machine;a godet having an inductively heatable shell; a drive motor and a driveshaft connecting said godet to said motor; bearings supporting saiddrive shaft; an electronic frequency inverter for generating three-phasepower for said motor; a stationary induction heater for heating saidgodet shell; an electronic heating power supply foresaid inductionheater; cooling means for cooling said motor, said frequency inverter,said electronic heating power supply and at least one of said bearings;at least one first temperature sensor for sensing the temperature ofsaid godet shell; at least one second temperature sensor for sensing thetemperature of one of said bearings; a microcomputer operating as afeed-back controller for controlling the temperature of said godet bycontrolling the energy supply to said induction heater; first terminalmeans for supplying a DC voltage to said frequency inverter; secondterminal means for supplying AC current to said induction heater; andthird terminal means for connecting said microcomputer to a data busleading to an external process computer, wherein said microcomputerfurther compares output signals of said first and second temperaturesensors with predetermined limit signals and provides an alarm signal ifone of said predetermined limits is exceeded.
 2. The godet assembly ofclaim 1, comprising two of said second temperature sensors for sensingthe temperatures of the inner and of the outer race of said bearing,wherein said microcomputer generates an alarm signal, if the temperaturedifference between the inner and the outer race exceeds a predeterminedlimit.
 3. The godet assembly of claim 2, wherein said microcomputeroperates as a feed-back controller for further controlling thetemperature difference between the inner race and the outer race of saidat least one bearing by controlling said cooling means.
 4. The godetassembly of claim 1, comprising an asynchronous drive motor and a speedsensor for sensing the rotational speed of said shaft, wherein saidmicrocomputer operates as a feed-back controller for further controllingthe rotational speed of said godet shell by controlling the outputfrequency of said frequency inverter.
 5. The godet assembly of claim 1,having said frequency inverter and said microcomputer incorporated intoa sealed housing which is directly attached to the housing of said drivemotor.
 6. The godet assembly of claim 1, with air cooling of the powerelectronics of said frequency inverter, wherein said power electronicsand said microcomputer are mounted on a heat conducting cooling blockwhich is attached to a protective housing in good heat transfer contact.7. The godet assembly of claim 6, wherein a blower wheel of a coolingblower, in axial direction of the drive shaft, is located between saiddrive motor and said cooling block.
 8. The godet assembly of claim 7,wherein said blower wheel is fixed to said drive shaft.
 9. The godetassembly of claim 7, comprising a blower motor driving said blowerwheel.
 10. The godet assembly of claim 6, wherein the power electronicsof said frequency inverter are mounted on a first support surface ofsaid cooling block and said microcomputer is mounted on a second supportsurface lying opposite said first support surface.
 11. The godetassembly of claim 6, having said cooling block attached to that frontwall of the motor housing which is remote from said godet.
 12. The godetassembly of claim 6, comprising a thermally and/or mechanicallyinsulating intermediate layer provided between said cooling block andits carrier.
 13. The godet assembly of claim 6, comprising a sealedprotective hood surrounding said cooling block.
 14. The godet assemblyof claim 1, wherein said protective housing is cylindrical and isprovided with cooling ribs extending in axial direction.
 15. The godetassembly of claim 1, with liquid cooling of the power electronics ofsaid frequency inverter, wherein said power electronics and saidmicrocomputer are carried by a hollow cooling block through which saidcooling liquid flows.
 16. The godet assembly of claim 15, wherein thehousing of said drive motor, in axial direction of said drive shaft, islocated between said cooling block and said support means and isprovided with coolant channels or a circular coolant gap.
 17. The godetassembly of claim 16, further comprising coolant channels for coolingsaid bearings.
 18. The godet assembly of claim 16, further comprisingadditional coolant channels in or adjacent to said induction heater. 19.The godet assembly of claim 16, wherein said godet is fixed to an end ofsaid drive shaft by means of a hub and further coolant channels areprovided in the region of said hub.
 20. The godet assembly of claim 10,having a system of cooling passages of such a configuration that thecoolant initially flows through said cooling block, then through coolingpassages around said drive motor, then through an annular spacesurrounding said hub and then through further cooling passages adjacentsaid induction heater and said bearings before it flows to the coolantoutlet. the slip frequency of said drive motor, simultaneously achievessynchronous speed control of said drive motor.
 21. The godet assembly ofclaim 15, further comprising a bearing housing carrying at least thatbearing which is remote from said motor, wherein said bearing housing,at least partially, is surrounded by said induction heater.
 22. Thegodet assembly of claim 15, having two spaced apart shaft bearings,wherein the shaft bearing further from said drive motor is disposedinside said induction heater and is carried by a tube-like bearinghousing surrounding said drive shaft, with said bearing housing beingsupported by a support flange provided for attaching said godet assemblyto the machine frame.
 23. The godet assembly of claim 22, wherein saidbearing housing simultaneously supports part of said induction heater.24. The godet assembly of claim 23, wherein said induction heatercomprises an inductor core which is carried by an inductor support tubewhich is attached to said support flange.
 25. The godet assembly ofclaim 24, having a circular gap between said inductor support tube andsaid bearing housing, wherein said circular gap is sealed at both axialends by resilient sealing means, which simultaneously provides vibrationdamping between said inductor core and said bearing housing.
 26. Thegodet assembly of claim 23, wherein one of said bearings is located inthe region of said support flange.
 27. The godet assembly of claim 1,wherein the bearing remote from said drive motor is locatedapproximately at the center of gravity of said assembly.
 28. The godetassembly of claim 1, comprising an asynchronous drive motor, whereinsaid microcomputer, by evaluating the slip frequency of said drivemotor, simultaneously achieves synchronous speed control of said drivemotor.
 29. The godet assembly of claim 28, wherein said microcomputer,for determining the draw force acting upon a yarn being advanced by saidgodet, measures a slip of said asynchronous drive motor and therewithmeasures its torque.
 30. The godet assembly of claim 1, comprising arotating measuring signal transmitter for transmitting temperaturesignals from said rotating first temperature sensor to the stationarymicrocomputer, dependent on the rotational speed of said drive shaft,which is used by said microcomputer for speed control of said drivemotor.
 31. The godet assembly of claim 1, wherein said microcomputerdelivers electrical signals indicative of at least one further physicalor electrical parameter of said godet, including vibrations, coolingwater temperature, drive motor temperature, drive motor current andheater current, and supplies corresponding alarm or safety shut-downsignals.